First off all, thank you all for your posts and information. Been lurking here and have read some good input over the last year.

I have a 2016 F-150 502a and was wondering if the transfer case/front diff/hubs lock into gear when the tranny is in park? The reason I ask is because I almost ran myself over today.

While at work I was coming down a single lane dirt/gravel road and come upon a co-worker. I thru it in reverse and backed up a steep spur road to allow the pass. The put it in park, set the e-brake to get out and talk with my co-worker. As I opened the door and released the foot break the truck rolled down the hill. It kinda freaked me out, but I moved the truck to more level ground to park. After I got and talked with my co-worker I started thinking and tried it again. Keep in mind I was in 4L. I backed up the spur road (mostly dirt with little gravel), checked my off-road indicator ( 22% decline) put the tranny in park, set the e-brake. What do you know, the truck rolled down the incline...rear tires sliding and the front tires rolling. Truck stopped after the decline decreases to approx 12%. Now I understand with the steep decline and loose surface conditions, just an e-brake on the rear tires might not hold me but I was in 4L.

So my question is: Is the transfer case and hubs supposed to lock when in park? I'd hope that I could park this truck on the same incline/decline that it traveled on. I couldn't imagine if I had a trailer and was in a bind for a similar senecio.

 

Does your transfer case have the 4A setting? If so I think that TC has clutches for engaging the front drive rather than gear engagement as old-school TC's did. Not sure what the clutches would do in park.

 

T-case doesn't lock in park, it doesn't have a 'park gear' or whatever the case may be.

 

Although the transfer case doesn't have a park lock, if in 4L it should be "locked" front to back.

Does the parking brake only lock one rear tire or both?

OP, was the engine still on when it rolled?

 

I do have the 4A option and have read it operates by a clutch. I would have assumed the clutch would stay engaged while in 4H or 4L when parked.